This invention relates generally to authentication and identification of objects, where identification in this context is used to mean recognizing to an acceptable degree of confidence an instance of an object. Objects may be any sort of object, and may themselves be associated with items, goods, people, animals, materials, and so on.
In security systems, there are many candidate identification technologies, including biometric technologies such as fingerprints, retinal scans, iris scans, and facial recognition algorithms. Biometric identification information is used to verify a unique identity.
One example of a conventional technology utilized to identify objects is Radio Frequency Identification (RFID) technology. With conventional Radio Frequency Identification (REID) technologies, an interrogator containing a transmitter generates an electromagnetic field through which an electronic tag containing a receiving antenna may pass. The electromagnetic field energizes the circuitry on the tag, which then transmits an identification number or code. Other functionality, such as data storage, or computation, also may be implemented on the tag.
Such technology may be used to identify objects, because, typically, an identification number communicated by the tag when it is energized is selected to be substantially unique, at least within the particular domain, and so the transmitted identification number may serve to identify the goods or people with which an object containing the tag is associated.
Such technology also may be used to authenticate (i.e., to verify) the identity of a person, animal, or thing associated with a tag, within a desired degree of confidence, if the tag is treated as evidence of the identity of such person, animal, or thing.
Generally speaking, RFID technology is useful for authentication only to the extent that it is difficult for a would-be forger or impersonator to replicate the behavior of a given tag, by manufacturing a duplicate tag, or otherwise. In many cases, the design of RFID tags is well known, and the technology is such that they may be duplicated. Some RFID tags exist that have encryption or other cryptographic functionality, but such tags are expensive, and the processing power on the tags is limited. As a result, it may not be feasible or cost-effective to maintain the security of a conventional RFID identification system against a determined attacker.